Device for locking up flexible printing plates on forme cylinders of printing presses

ABSTRACT

The invention relates to a device for locking up flexible printing plates on forme cylinders of printing presses in which the printing plate is fastened detachably at its one axially extending first end to a first edge of a cylinder groove and its second end is connected with a spring fastener, the resilience of which can be released by means of a rotatable longitudinal shaft.

United States Patent Dauner et al.

[1113 3,913,480 14 1 Oct. 21, 1975 Wurzburg; Karl-Heinz Arno Wolfram, Eibelstadt, all of Germany Koenig & Bauer Aktiengesellschaft, Wurzburg, Germany Filed: Apr. 17, 1973 Appl. N0.: 351,939

Published under the Trial Voluntary Protest Program on January 28, 1975 as document no. B 351,939.

Assignee:

Foreign Application Priority Data May 23, 1972 Germany 2225016 us. 01 101/41s.1; 101/378 1111. 01. B41F 27/02 Field of Search 101/415.1, 378

References Cited UNITED STATES PATENTS 5/1955 l-Iarless 101/378 10/1956 Park et al. 101/415.1 '10/1956 Fies 101/415.l

3,019,728 2/1962 Wenczler 101/378 3,043,219 7/1962 Dietrich 101/378 3,095,811 7/1963 Peabody et al. 10l/415.1 3,107,609 10/1963 l-Iaramija 101/378 3,335,663 8/1967 Harenza l01/415.1 3,603,255 9/1971 l-Iorner 101/415.1 3,625,151 12/1971 Hart 101/4l5.1 3,626,848 12/1971 Tafel 101/415.1 3,757,691 9/1973 Etchell 101/387 FOREIGN PATENTS OR APPLICATIONS 1,200,991 8/1970 United Kingdom 101/378 1,231,188 5/1971 United Kingdom 101/415.1 1,263,021 3/1968 Germany 101/378 52,380 12/1966 Germany 101/415.1

53,708 2/1967 Germany l01/415.1

Primary Examiner-Robert E. Bagwill Assistant ExaminerWilliam Pieprz Attorney, Agent, or FirmJones, Tullar & Cooper 5 7 ABSTRACT The invention relates to a device for locking up flexible printing plates on forme cylinders of printing presses in which the printing plate is fastened detachably at its one axially extending first end to a first edge of a cylinder groove and its second end is connected with a spring fastener, the resilience of which can be released by means of a rotatable longitudinal shaft.

3 Claims, 4 Drawing Figures US. Patent Oct. 21, 1975 Sheet 1 of 4 3,913,480

US. Patent Oct. 21, 1975 Sheet2 of4 3,913,480

US. Patent Oct.21, 1975 Sheet4 of4 3,913,480

DEVICE FOR LOCKING UP FLEXIBLE PRINTING PLATES ON FORD/IE CYLINDERS OF PRINTING PRESSES THE PRIOR ART Devices of this kind have already become known.

In the German Patent Specification No. 1,178,442 a device is described in which the spring fastener consists in a leaf spring 260 with a curve-like part 26a. It seems, however, that the plate end is not guided in a sufficiently rigid and precise manner.

SUMMARY OF THE INVENTION It is the object of the present invention to create a device by which the position of the printing plate ends is fixed exactly, by means of which the printing plate can be adjusted in circumferential register, and which requires only a small blank space and flat channels, so that the cylinder is reduced only a little bit.

According to the present invention, this object has been solved in such a manner that the first end of the printing plate is capable of being fastened to a first locking plate capable of swinging on a first hinge and that the other fastener consists of a second locking plate capable of swinging on a second hinge.

In a further development of the invention it is suggested that the locking plates be supported in hinge joints.

An embodiment of the invention is diagrammatically illustrated, by way of example, with reference to the accompanying drawings.

FIG. 1 is a cross section of the device, the plate being fixed in position,

FIG. 2 is a cross section in released position,

FIG. 3 is a section of III III in FIG. 4, and

FIG. 4 is a plan view on a reduced scale.

Into a forme cylinder 1 an axially extending cylinder groove 2 is provided in which a device for locking up a flexible printing plate 3 is fastened.

The said device consists among other parts in a locking plate 4, which extends over the width of the printing plate 3 and has at its one end some lock up hooks 5. These lock up hooks 5 are received in holes 6 in the printing plate 3. The other end of the locking plate 4 is forming, together with a semicircular formed end of a hinge plate 9, a hinge 7 on which it is capable of swinging. By pressure applied by a leaf spring 8 the locking plate dis swung into a position in which the printing plate 3 is fixed. By means of screws threadedly received in apertures at the bottom of groove 2 in forme cylinder 1 a hold down bar 21 through which the screws extend holds the hinge plate 9 down on the lower end of leaf spring 8 at the bottom of groove 2. The hold down bar It) extends substantially the length of each locking plate. The hinge plate 9 has a semicircular portion 11 at its other end so as to form with the lower end of another locking plate 13 a hinge joint 12. The locking plate 13 ends on the other end in fixing hooks 14 to which the first end of the printing plate 3 is hung by means of holes 6 formed therein as in the other end of the printing plate 3.

The locking plate 13 is pressed by a spring 16 received in a transversely extending recess in bar 21 to a first border or abutment 2.1 in the adjacent wall portion of the cylinder groove 2. In this position it rides against a cam 17 on a longitudinal shaft 18. By rotating the longitudinal shaft 18 or the cam 17 respectively the locking plate 13 is swung around the hinge 12, and thus the printing plate 3 is shifted in circumferential direction contrary to the effect of the spring 16.

A half-side milled longitudinal shaft 19 is received in a longitudinal recess in bar 21 with the half-side parallel to locking plate 4. By rotation of the shaft 19 the locking plate 4 is moved contrary to the effect of the spring 8 until it fits against a second border or abutment 2.2 in the upper portion of the side wall of the cylinder groove 2. In this position the plate 3 can be hung easily into the fixing hooks 5. For the purpose ofinserting the printing plate 3, the cam 17 of the registering device can be set to zero position (see FIG. 2).

FIG. 3 shows a section III III of the device. The longitudinal shaft 18 ends in a hexagon 22 and the longitudinal shaft 19 in a hexagon 23. The longitudinal shaft 19 is supported in the bar 21 in which also the spring 16 is positioned.

In FIG. 4 a plan view is shown, from which is to be seen that the hexagons 22, 23- are accessible by means of notches 24, 25 which are milled into the forme cylinder 1 in circumferential direction.

The device enables the disposition of as many lock up devices as required over the width of a cylinder, because actuation by the hexagons 22, 23 can be realized close to the printing plate and the hexagons 22, 23 are disposed in the area of the blank white margin.

The plate ends are guided precisely by the locking plate 4, 13. The forces having an effect on the longitudinal shafts l8, 19 are absorbed over the whole length of the shafts by the support in the cylinder 1 or in the bar 21 respectively.

What is claimed is:

l. A device for detachably holding flexible printing plates on forme cylinders of printing presses, said device comprising in combination:

a forme cylinder having an axially extending groove in its periphery;

a first locking plate rotatably positioned in said groove, said first locking plate extending substantially the width of said printing plate, saidfirst locking plate having an axially extending hinge portion at its lower end and hook portions on its upper end, said hook portions being receivable in apertures in a first end of said printing plate; hold down bar secured in said groove; first cam means rotatably carried in an axially extending recess in said hold down bar, said first cam means and said hold down bar extending substantially the length of said groove, said first cam means having wrench receiving means on an end thereof for rotating said first cam means to cause said first cam means to press against a first side of said first locking plate throughout its length; leaf spring having a transversely extending bottom end positioned in said groove beneath said hold down bar and having an upper end which presses against a second side of said first locking plate, said first cam means and said leaf spring holding said first end of said printing plate in a selected position; a second locking plate rotatably positioned in said groove opposite said first locking plate, said second locking plate extending substantially the width of said printing plate, said second locking plate having an axially extending hinge portion at its lower end and hook portions on its upper end, said hook portions being receivable in apertures in a second end of said printing plate;

second cam means rotatably carried in a wall of said groove and having wrench receiving means on an end thereof for rotating said second cam means to cause said second cam means to press against a first side of said second locking plate throughout its length;

spring carried in said hold down bar and pressing against a second side of said second locking plate, said second cam means and said spring holding said second end of said printing plate in a selected position; and

hinge plate, said hinge plate having semicircular end portions opening downwardly to secure said is secured in said groove by screws extending through said bar and being threadably received in said forme cylinder.

3. The device of claim 1 wherein said second cam means further includes a vernier scale means whereby the position of said second cam means may be accurately determined. 

1. A device for detachably holding flexible printing plates on forme cylinders of printing presses, said device comprising in combination: a forme cylinder having an axially extending groove in its periphery; a first locking plate rotatably positioned in said groove, said first locking plate extending substantially the width of said printing plate, said first locking plate having an axially extending hinge portion at its lower end and hook portions on its upper end, said hook portions being receivable in apertures in a first end of said printing plate; a hold down bar secured in said groove; a first cam means rotatably carried in an axially extending recess in said hold down bar, said first cam means and said hold down bar extending substantially the length of said groove, said first cam means having wrench receiving means on an end thereof for rotating said first cam means to cause said first cam means to press against a first side of said first locking plate throughout its length; a leaf spring having a transversely extending bottom end positioned in said groove beneath said hold down bar and having an upper end which presses against a second side of said first locking plate, said first cam means and said leaf spring holding said first end of said printing plate in a selected position; a second locking plate rotatably positioned in said groove opposite said first locking plate, said second locking plate extending substantially the width of said printing plate, said second locking plate having an axially extending hinge portion at its lower eNd and hook portions on its upper end, said hook portions being receivable in apertures in a second end of said printing plate; a second cam means rotatably carried in a wall of said groove and having wrench receiving means on an end thereof for rotating said second cam means to cause said second cam means to press against a first side of said second locking plate throughout its length; a spring carried in said hold down bar and pressing against a second side of said second locking plate, said second cam means and said spring holding said second end of said printing plate in a selected position; and a hinge plate, said hinge plate having semicircular end portions opening downwardly to secure said hinge portions of said first and said second locking plates, said hinge plate being positioned in said groove beneath said hold down bar and above said transversely extending bottom portion of said leaf spring.
 2. The device of claim 1 wherein said hold down bar is secured in said groove by screws extending through said bar and being threadably received in said forme cylinder.
 3. The device of claim 1 wherein said second cam means further includes a vernier scale means whereby the position of said second cam means may be accurately determined. 